Safety-grip for elevators.



I c. K. ROGERS.

SAFETY GRIP FOR ELEVATORS.

APPLICATION FILED MAE. 3, 1910.

Patented Oct. 11,1910.

3 SHEETS-SHEET l.

G. K. ROGERS;

SAFETY GRIP FOR ELEVATORS.

APPLIGATION FILED Emma, 1910.

3 SHEETS-SHEET 2.

:lllllllli 34 m w 4 /l/i/f/ M 4 Witnesses.

PETERS 0-, wAsHmamN n c C. K. ROGERS.

SAFETY GRIP FOR ELEVATORS. APPLICATION FILED MAR.3, 1910.

Patented Oct. 11, 1910.

With/69s s as. W [711/ 672/260 7? COLUMBUS K. ROGERS, OF SALEM, MASSACHUSETTS.

SAFETY-GRIP FOR ELEVATORS.

Specification of Letters Patent.

Patented Oct. 11, 1910.

Application filed March 3, 1910. Serial No. 546,989.

To all whom it may concern.

Be it known that I, COLUMBUS K. ROGERS, a citizen of the United States, residing at Salem, in the county of Essex and State of Massachusetts, have invented new and useful Improvements in Safety-Grips for Elevators, of which the following is a specification.

This invention relates to a safety device for elevator-cars, the object of the invention being to provide a safety grip consisting of two gripplng segments arranged on opposite sides of the guide strip for the elevator car, these grips being connected together by segment gears, said grips being so arranged as to ordinarily be out of contact with the guide strips and one of the safety grips being connected to a lever which is operated when the hoisting cable of the elevator car breaks to draw the toothed peripheries of the grips into engagement with the guide strips, and the toothed peripheries of said grips being eccentric to their pivotal centers, said grips will automatically bind upon opposite sides of the strips respectively and prevent the elevator car from falling.

The invention is particularly directed to the grips with their segment gears and to the plate or guide upon which these grips are pivotally mounted.

The invention is further particularly directed to the improved mechanism by which the grips are brought into engagement with the guide strips prior to the gripping operatlon.

The invention consists in the combination and arrangement of parts set forth in the following specification and particularly pointed out in the claims thereof.

Referring to the drawings: Figure 1 is a perspective View of an elevator car with my improved safety device attached thereto, the same being partly broken away for the sake of clearness of illustration. Fig. 2 is a perspective view on an enlarged scale of one air of grips and their segment gears showstuds and also showing the guide plate to which the bearing studs are fastened. Fig. 3 is a section, partly in plan, taken on line 33 of Fig. 2; with the grippers removed. Fig. 4: is a plan view of the bearing plate or lower guide. Fig. 5 is a plan view of the gripping dogs with their segment gears, with the guide strip shown in section. Fig. 6 is a front elevation of said grip dogs and mg the same mounted upon the bearing their segment gears, and the guide strip shown in relation thereto. Fig. 7 is a side elevation of the connecting rod broken away to save space, showing the same in connection with the outer end of the gripper actuating lever, also broken and shown in section. Fig. 8 is a plan view of the outer end of the gripper actuating lever and the connecting rod.

Like numerals refer to like parts throughout the several views of the drawings.

In the drawings, 5 is an elevator car of any suitable construction having a floor 6, side bars 7, 7 and cross-beam 8. The elevator car is guided in the well in the usual manner by means of guides 9 and 10 fastened near the top and bottom of the elevator car respectively, and these guides are duplicated upon opposite sides of the elevator car. The guides 9 and 10 are provided with guideways 9 and 10 to receive the guide-strips 11, 11 fast to the inner faces of the uprights 12, 12.

It will be understood that the mechanism for operating the grip dogs, as well as the grips, is duplicated upon opposite sides of the elevator car, so that there is a pair of grips and a pair of segment gears upon each side of the elevator car and these grips and grip gears act simultaneously on opposite sides of the elevator car and are actuated by mechanism which is practically in duplicate for the two sides. Therefore, the description which follows for the safety device mechanism upon one side of said elevator car applies equally well to the safety device mechanism upon the opposite side of said elevator car. I

The upper guide 9 is of usual construction and is securely fastened to the side bar of the elevator car. The lower guide 10 is of special construction and constitutes an important part of my invention. This guide 10 consists of a plate 13 which is fastened to the elevator car near the bottom thereof and has a rib 14 extending rearwardly therefrom which projects beneath the floor framing and bears thereagainst and is fastened thereto by bolts which pass through holes 24, 24 in said rib 14, so that when the elevator car drops and the strain of stopping the momentum of the same comes upon this plate, the strain will not be transmitted through the grips and through'the screws which hold the plate to the elevator car, but will, in a. large measure be taken by the solid for the grip dogs 16, 17'.

casting of the plate 13 which extends beneath the elevator car in the form of the rib let. Two bearing studs 15, 15 are fast to the plate 13 preferably by casting said studs in said plate, these studs serving as pivots pass through the holes 24, 2st also pass through the sides of the studs 15, 15, thus assistingto lock them in place.

' studs 15, 15", but -the toothed peripheries of the grip dogs 16 and 17 are eccei'itric to said bearing studs, as will be seen by reference to Fig. 6. To limit the do'wi'iward movement of the grip dogs and the segment gears,

and to prevent the segmei'it gears from get.-

ting -outof mesh, stop-screws 20, 20 are provided in the grip dogs and the inner ends of these stop-screws project into annular grooves 2 1, 21 in th'e bearing studs 15, 15. Stop-pins 22, '22 are also provided in these annular grooves, so that the ends of the stopsc'rews abut against these bearing pinsafter the grip dogs have dropped to about the position illustrated in Fig. 6, and are thus prevented from moving downwardly relatively to each other any farther, and passing out of mesh with each other. The stopscrews perform the further function of preventing the grip dogs from moving longitudinally relatively to their hearing studs.

A great strain is brought to bear upon the bearing studs 15, 1-5 when the grip dogs are in operation to bind upon the guide strips and stop the elevator car and this strain tends to break the guide plate, 1 3, so that the same is, in my construction, reinforced by means of a link 23 which is cast in the plate 13, as illustrated particularly in F 3, and extends around the bearing pins, joining them together and imparting great strength to the structure as a whole to prevent the plate 1 3 from being split apart when the strain liereinbefore referred to is brought to bear thereon.

I will now proceed to describe the mechanisin by means of which the grip "dogs are brought into engagement with the guide strips. The elevator car is hoisted and lowered in the usual manner by means of a cable (not shown), but which is fastened to "a slide 25 at the upper end thereof. The slide 25 is arranged to slide in p'la tes'26, '26 fast to the top and bottom of the cross beam 8.

Said slide 25 is provided with ahead 27 at the lower end thereof, which, when the e'le vator car is in use and in practical operation, abuts against -thebot-tom o' f 'the lower plate 26 hen, however, an "accident happens and the hoisting cable l'w-ealis, -then the slide The bolts which:

25 is moved downwardly by the spring 28 which passes through. the head 27 of said slide and bears at its outer ends against the under side of the cross-beam S. The slide 25 has connected thereto two levers 29, 29, one of which operates the grips upon one side of the elevator car, the other operating the grips on the opposite side of the elevator car. Taking, then, one of these levers we find that the same is pivoted at 30 to the cross-beam S and has extending therethrough at its outer end a slot 31, and through this slot- 31 projects the upper end of a connecting rod 32 which is flatted ofi' at. 33 where said rod projects through said slot.

A head 34 is provided on the upper end of this connecting rod and the connecting rod, as a whole, consists of the upper part 35 and the lower part 36. The lower end of the upper part- 35 is screw-threaded to engage the lower part 36 and has a lock-nut 37 thereon to prevent rotation of the upper and lower parts relatively to each other. Such rotation is further prevented by the flattened upper cut 33 where it projects through the slot 31 and by the lower part 36 projecting into a recess 38 in the upper side of the grip dog 17, said lower part 36 being piv'otally connected to said grip dog by means of a pivotal pin 39.

The general operation of the device hereinbe'fore specifically described is as follows: Assuming the hoisting cable to break and the elevator car to begin to fall, immediately upon the breaking of the cable the slide 25 will be forced downwardly by the spring 28, thus rocking the levers 29, 29 upon their pivots and moving the connecting rods on opposite sides of the elevator car upwardly upon each side of the elevator car, thus drawing the grip dog 17 upwardly, and as said dog is connected by the segment gears 18 and 19 to the grip dog 16, it follows that the grip dogs will simultaneously be moved upwardly until said grip dogs 16 and 17 engage 'the guide strips 11. Then, by reason of the eccentric arrangementof the toothed peripheries of the grip dogs, the weight of the elevator car will cause said grip dogs to bite into the guide strips upon opposite sides thereof and absolutely wedge the same, so that the elevator car cannot move downwardly.

The operation of the grip dogs and the mechanism which controls them is the same upon opposite sides of the elevator car, as herei-nbefore set forth, it being understood that the grips on one side grip one of the guide strips and the grips on the opposite side grip the other guide strip.

l-la'vingthus described my invention, what I claim and desire by Letters Patent to secure is:

1. An elevator safety device having, in combination, an elevator car, guide strips therefor, guides fast to said elevator car adapted to engage said guide strips, a pair of grip dogs pivotally mounted on one of. said. guides upon opposite sides of one of said guide strips, gears integral with said grip dogs meshing into each other, means movable 011 said elevator car, whereby said elevator car may be hoisted, and mechanism connecting said movable means to one of said grips, whereby when said means is moved relatively to said elevator car said grips are brought into engagement with one of said guide grips.

2. An. elevator safety device having, in combination, an elevator car, guide strips therefor, guides fast to said elevator car adapted to engage said guide strips, a pair of grip dogs pivotally mounted upon one of said guides upon opposite sides of one of said guide strips, gears integral with said grip dogs meshing into each other, a slide movable vertically on said elevator car, a stop therefor, and slide adapted to be connected to a hoisting cable, whereby said elevator car may be hoisted, a spring adapted to move said slide downwardly, a lever connected to said slide, and a rod connecting said lever to one of said grips, whereby when said slide is moved relatively to said elevator car said grips are brought into engagement with one of said guide strips.

3. An elevator safety device having, in combination, an elevator car, guide strips therefor, guides fast to said elevator car adapted to engage said guide strips, a pair of grip dogs pivotally mounted upon one of said guides upon opposite sides of one of said guide strips, gears on said grip dogs meshing into each other, a slide movable vertically on said elevator car, a stop therefor, said slide adapted to be connected to a hoisting cable, whereby said elevator car may be hoisted, a spring adapted to move said slide downwardly, a lever connected to said slide, and a rod connecting said lever to one of said grips, said rod formed in two parts, the upper part fiatted at its upper end, said fiatted end projecting through a. slot provided in said lever, the lower end of said upper part having screw-threaded engagement with said lower part, and said lower part pivotally connected at the lower end thereof to one of said grips, whereby, when said slide is moved relatively to said elevator car, said grips are brought into en gagement with one of said guide strips.

4:. An. elevator safety device having, in combination, an elevator car, a guide strip therefor, a guide fast to the lower end of said elevator car and consisting of a. plate with a vertical guideway formed therein adapted to receive one of said strips, two bearing studs extending laterally of said plate from the outer face thereof upon opposite sides of said guide strip, a pair of grip dogs pivotally mounted upon said bearing studs, gears on said grip dogs meshing into each other, and stop screws in said grip dogs, the inner ends of which project into annular grooves provided in said bearing studs. v

5. An elevator safety device having, in combination, an elevator car, a guide strip therefor, a guide fast to the lower end of said elevator car and consisting of a plate with a vertical guideway formed therein adapted to receive one of said strips, two bearing studs extending laterally of said plate from the outer face thereof upon opposite side of said guide grip, a pair of grip dogs pivotally mounted upon said bearing studs, gears on said grip dogs meshing into each other, stop screws in said grip dogs the inner ends of which project into annular grooves provided in said bearing studs, and stop pins in said grooves against which the inner ends of said stop screws are adapted to abut, whereby the downward movement of said grip dogs relatively to each other is limite 6. In a device of the character described, a guide consisting of a plate with a vertical guide-way formed therein, two bearing studs projecting laterally from the outer face of said plate, and a link extending around said studs and cast in said plate.

7. In a device of the character described, a guide consisting of a plate with a vertical guideway formed therein, two bearing studs projecting laterally from the outer face of said plate, a link extending around said studs and cast in said plate, and a pair of grip dogs pivotally mounted upon said hearing studs and gears on said grip dogs meshing into each other.

In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses.

COLUMBUS K. ROGERS. Vitnesses TERRANOE J. NoL-AN, J. CLIFFORD EN'rwIsLE. 

